ceiling. treasury officials say it's illegal to mint a coin for a purpose like that. >>> he's considered one of the greatest cyclists of all-time but hanging over his head are charges of doping to achieve that success. now lance armstrong may be coming clean about drug use during his tour de france races. abc news reporter mark greenblat has the latest. >> in his last interview with oprah nearly two years ago, lance armstrong got a hero's welcome. now disgraced and labeled as a cheater, he will face a much tougher audience when he sits with her again. but if, as expected, armstrong confesses to doping, it would likely come only after the statute of limitations on perjury charges ran out. following this strong denial under oath. >> i just want to make sure your testimony is clear. if it can't be any clearer that i've never taken drugs. >> still an about-face could land hem in serious hot water. he's still facing an ongoing federal whistle blower's suit that's tightly under seal and another suit